Limp mode Octavia 19 TDI

[octaviadan]

Sorry to resurrect a slightly old post but thought I would update you re my Octavia.

One of my previous posts I loaded up a boost log, which looked fine to me and was confirmed by mbames et al that this all looked good. A couple of weeks previous to the boost log I did change the final thing which can cause boost issues on our TDi's which was the MAP sensor on top of the intercooler (I also flushed this out but was not fouled in any way), even though there were no issues logged with the performance of the MAP according to VCDS.

Anyway I did some of the final checks as suggested including the VNT mechanism checks and also the TDi timing on VCDS, all of which are working or set as it should be. Following this I have since been away on a family hoilday to Suffolk so a good long fast run on A1 and A14 etc there and back and it ran absolutely perfect - best it has ever performed!

A couple of weeks have passed since and my Octy is back into its usual weekly running routine and I have to say that it is still running very well - picking up and boosting all through the rev range as I imagine it should do - it really does seem to drive like a new car! Also I have noticed an improvement with fuel consumption as I now get 500+ miles on a full tank before the light comes on (before it was 450 - 470 at best).

I think I can conclude that at last that I have finally solved the boost/performance issue, following fitting a new MAP sensor.

So if you have replaced everything else as I have to try and get your TDi running and performing as it should, replace the MAP sensor on top of the intercooler with a new fresh one - they only cost about £25 and it may finally solve your problems....

Finally just want to say thanks to eveyone for their help and advice, all very much appreciated

Dan

Edited 15 September, 2012 by octaviadan

[mbames]

£25 for a MAP sensor? I think I am prepared to change mine, as the car is now over 200k.

Aren't they a right pig to change though? I started trying to mine out once and then gave up (was meant to be changing my cambelt at the time!)

[Lofty79]

Access looks easy to me, behind offside headlight, two torx bolts. Might do mine.

[octaviadan]

Mbames, it would be a PITA to change the MAP in situ.

The easiest way to do it is to remove the intercooler. I removed the front bumper, o/s headlight and indicator to get easy access to the intercooler mounting bolts. This is quite a easy task and only takes about 20 mins or so to remove all this. The trickiest bit is removing those strong spring clamps which hold the boost pipes onto the intercooler.

Once the intercooler is off, try the MAP sensor mounting screws as they can be very tight as the screws can rust into the plastic body of the IC so you can easily chew up the screw heads..I was lucky with mine as they loosened and came out no problem.

Give the IC a good clean by flushing it through with some solvent like carb/brake cleaner or petrol and make sure it is fully dry before refitting.

Re-assemble everything in reverse order to removal making sure to reconnect all electrical plugs. You might find that bottom IC mounting bolt a bit of a pig to put back in - I managed to strip the threads on that one!

Once all back together, before you start back up, remove the top intake pipe at the EGR side and start without this connected. Engine will sound very loud but this will ensue that the boost pressure blows through any remnants of solvent cleaner in the IC without it entering into the intake manifold.

I am sure you will notice an immediate improvement but I think sometimes with these cars it takes a 1000 miles or so before all settles down and the ECU is used to its new 'settings'.

Let us know how you get on!

Dan

[Lofty79]

I just put a screw driver in and undid it.......just now, took 5 mins. Why did you have to take your bumper off?

[octaviadan]

It looked a bit awkward to get at and as I wanted to clean the IC it was the best way for me.

Wasn't awkward or difficult or particularly time consuming I think it took me just over an hour including flushing out and cleaning the IC.

[Lofty79]

ah yes, flushing IC. May have a go myself

[robo_1]

Hey guys...

Mr Muscle is going to get a rude awakening today...

Time for another Turbo clean out.. (Not sure if i done a good enough job last time)..

Car started jumping around, just as the turbo was about to kick in 1200 rpm to about 1900 rpm (Thought i had kangaroo diesel), Thats when i knew it was time..

Trouble is i left it progress..

Untill Today.... LIMP MODE......... Arrrrrrrrragh

But a quick on and off of the ignition sorted that until i got home...

So fingers crossed the rain stays away tomorrow.. :sweat: I`ll clean it until you could eat you dinner off of it...

Will keep you all posted on success... :giggle:

[Lofty79]

I whip of downpipe and spray it in there too for a good clean. 2hrs is key

[robo_1]

I whip of downpipe and spray it in there too for a good clean. 2hrs is key

Ok, will do... Will keep you posted .... :think: :think:

[mbames]

Hey guys...

Mr Muscle is going to get a rude awakening today...

Time for another Turbo clean out.. (Not sure if i done a good enough job last time)..

I had to re-treat mine a few weeks back too. It seems like Mr Muscle is only a temporary cure on my car :-( Still I guess I can live with it if I only have to clean it every 6 months or so.

Edited 21 November, 2012 by mbames

[FinlayF]

Hi All

I'd be very grateful for some guidance.

The info on this thread (and related threads) is enormously interesting because it seems to connect completely with the problem I'm having. My car goes into limp mode at about 3,300 rpm or under any heavy acceleration.  So, I've been dying to try the Mr Muscle remedy.

Went out and bought the Mr Muscle and plastic pipe, took a good look at the photos posted by Lofty79, and got the tools out last Sunday. That's when the problems began...

First, was access. The EGR valve and pipework is at the back of the engine and even getting the inlet manifold flap housing off took ages, and once off I could see that the pipe below the EGR valve didn't lead to the manifold but to what looked like an intercooler, so I wasn't sure how/if the Mr Muscle remedy could be used. I popped back indoors and scoured this forum for pics of Mr Muscle treatment on different engines but couldn't find anything. Even my Haynes manual shows a different EGR layout to the one I've got, so the removal instructions were useless!  I couldn't get any closer to look at the intercooler layout because there was no way I could shift the pipe bolts below the EGR valve - there was no room to get any tools in. Also, daylight was passing so I contented myself with cleaning a lot of gunk from the EGR while it was still fitted, and replacing everything. The car now drives differently (seems to have less boost at lower revs ...) but still goes into limp mode.

I saw a comment on this thread (I think from Lofty79) which mentioned something about intercoolers but I'm at a loss as to how to proceed.

Can anyone help me with some suggestions, please? Are there any pictures of Mr Muscle treatment on an EGR valve that connects to an intercooler? Where would the plastic pipe go, and where would the actuator be? Finally, what peripheral stuff needs to be removed to get enough access to take these parts off?

 

[FinlayF]

PS. Sorry, I should have stated that I know this thread relates to Mk1 models. I'm just hoping someone can help me with the same problem on a MK 2 Octavia. 

[FinlayF]

Polite bump.

[FinlayF]

I've now posted a guide to using Lofty79's Mr Muscle fix on an Octavia Mk 2 1.9 TDI

Sticky vanes Mr Muscle treatment on Octavia Mk 2 1.9 TDI.